ARJUNAWIWĀHA

The Arjunawiwāha is one of the best known of the Old Javanese classics. This volume presents a new text, based on Balinese manuscripts, with a complete translation, building on the work done by earlier writers. An introduction provides ample background information, as well as an original interpretation of the significance of the text, within its historical and cultural setting. This poem was written by Mpu Kanwa in around A.D. 1030 under King Airlangga, who ruled in East Java. It is Mpu Kanwa’s only known work, and is the second oldest example in the genre of kakawin. The poem is a narrative, but also contains passages of description, philosophical or religious teaching of great interest, as well as remarkable erotic scenes. Parts of the tale have been depicted on early temple reliefs and in paintings, ­­and the text is still recited in Bali by literary clubs and in temple ceremonies. Stuart Robson, Associate Professor of Indonesian at Monash University from 1991 to 2001 and now retired, has been studying Old Javanese for more than forty years. He is interested in the problem of how to translate works of Old Javanese literature in such a way as to make these more accessible and better known to a wider audience of both scholars and general readers

Systematic vertical error in UAV-derived topographic models:origins and solutions

Unmanned aerial vehicles (UAVs) equipped with consumer cameras are increasingly being used to produce high resolution digital elevation models (DEMs). However, although such DEMs may achieve centimetric detail, they can also display broad-scale systematic deformation (usually a vertical ‘doming’) that restricts their wider use. This effect can be particularly apparent in DEMs derived by structure-from-motion (SfM) processing, especially when control point data have not been incorporated in the bundle adjustment process. We illustrate that doming error results from a combination of inaccurate description of radial lens distortion and the use of imagery captured in near-parallel viewing directions. With such imagery, enabling camera self-calibration within the processing inherently leads to erroneous radial distortion values and associated DEM error. Using a simulation approach, we illustrate how existing understanding of systematic DEM error in stereo-pairs (from unaccounted radial distortion) up-scales in typical multiple-image blocks of UAV surveys. For image sets with dominantly parallel viewing directions, self-calibrating bundle adjustment (as normally used with images taken using consumer cameras) will not be able to derive radial lens distortion accurately, and will give associated systematic ‘doming’ DEM deformation. In the presence of image measurement noise (at levels characteristic of SfM software), and in the absence of control measurements, our simulations display domed deformation with amplitude of 2 m over horizontal distances of 100 m. We illustrate the sensitivity of this effect to variations in camera angle and flight height. Deformation will be reduced if suitable control points can be included within the bundle adjustment, but residual systematic vertical error may remain, accommodated by the estimated precision of the control measurements. Doming bias can be minimised by the inclusion of inclined images within the image set, for example, images collected during gently banked turns of a fixed-wing UAV or, if camera inclination can be altered, by just a few more oblique images with a rotor-based UAV. We provide practical flight plan solutions that, in the absence of control points, demonstrate a reduction in systematic DEM error by more than two orders of magnitude. DEM generation is subject to this effect whether a traditional photogrammetry or newer structure-from-motion (SfM) processing approach is used, but errors will be typically more pronounced in SfM-based DEMs, for which use of control measurements is often more limited. Although focussed on UAV surveying, our results are also relevant to ground-based image capture for SfM-based modelling

Determining the rheology of active lava flows from photogrammetric image sequence processing

We describe a photogrammetric approach used to determine the rheological properties of active lava flows based on stereo image sequences. Bulk rheological properties can be estimated from measurements of flow slope, velocity and dimensions and so, at flow-fronts, they can be calculated from sequential digital elevation models (DEMs) acquired as the flow advances over new ground. For useful flow parameters to be extracted, DEMs may need to be obtained at approximately minute intervals, over durations of up to multiple hours. To deliver such data, we use oblique stereo pair sequences captured by digital SLR cameras and a semi-automated DEM-generation pipeline. Although similar data could be acquired with a terrestrial laser scanner, with deployments in remote and hazardous regions the photogrammetric approach offers significant logistical advantages in terms of reduced equipment cost, bulk, weight and power requirements. We describe the application of the technique to an active lava flow on Mount Etna, Sicily, in 2006. Image sequences were acquired from two tripod-mounted cameras over a period of ~3 hours, as the flow-front advanced ~15 m. Photogrammetric control was provided by 11 targets placed in the scene, with their coordinates determined by dGPS. The cameras were synchronised by a shutter release cable and triggered by an external timer (intervalometer). Image pairs were obtained every minute with DEMs extraction carried out on every fourth epoch; 57 DEMs, with a 0.25-m resolution, were generated. We describe the challenges associated with data collection in this remote environment and the techniques required to automate the photogrammetric analysis and sequence-DEM generation

Tell Khaiber: An administrative centre of the Sealand period

Excavations at Tell Khaiber in southern Iraq by the Ur Region Archaeological Project have revealed a substantial building (hereafter the Public Building) dating to the mid-second millennium b.c. The results are significant for the light they shed on Babylonian provincial administration, particularly of food production, for revealing a previously unknown type of fortified monumental building, and for producing a dated archive, in context, of the little-understood Sealand Dynasty. The project also represents a return of British field archaeology to long-neglected Babylonia, in collaboration with Iraq's State Board for Antiquities and Heritage. Comments on the historical background and physical location of Tell Khaiber are followed by discussion of the form and function of the Public Building. Preliminary analysis of the associated archive provides insights into the social milieu of the time. Aspects of the material culture, including pottery, are also discussed

On virtual auras:The cultural heritage object in the age of 3D digital reproduction

Making three-dimensional (3D) models for public-facing cultural heritage applications currently concentrates on creating digitised models that are as photo-realistic as possible. The virtual model should have, if possible, the same informational content as its subject, in order to act as a ‘digital surrogate’. Many cultural heritage objects have, to borrow an old term, aura: an affectual power to engender an emotional response in the viewer. The term ‘digital surrogate’ is commonly used when talking about 3D models in cultural heritage applications. Exploring the meaning of this term is highly valuable. The E-Curator project and subsequent work by Mona Hess has demonstrated the potential for 3D scanning technology for professional cultural heritage (CH) purposes and there are clear advantages to working in the digital realm. Visitors to CH institutions—members of the public with no privileged access to the exhibits—will have a very different experience to that of a CH professional

Response to comment on "solid recovered fuel: Materials flow analysis and fuel property development during the mechanical processing of biodried waste"

Laner and Cencic1 comment on Velis et al. (2013)2 clarifying certain points on the use of the material flow analysis (MFA) software STAN3. We welcome the correspondence and the opportunity this exchange provides to discuss optimal approaches to using STAN. In keeping with Velis et al.2 these physically impossible, and otherwise insignificant, negative flows have enabled improvements to STAN. Here, we elaborate on the practicalities of using STAN in our research and on the correctness and validation of our results, notwithstanding the inclusion of negative flows. We explain the contribution of our approach to solid waste management and resource recovery